In the installation calculation, there is a project for HVAC, in which ventilation system is a very important part. With the ventilation system to say the operation method and precautions.
First of all, there are two methods in installation calculation of ventilation system, one is drawing mode, the other is conversion mode. This time, we will talk about the application of transformation mode.
This paper mainly emphasizes the precautions for the operation of air duct and air valve in ventilation system
1、 Identification of air duct
Before the conversion of duct, there is a content that must be clear first, that is, the elevation of duct. When viewing with the height adjustment command, sometimes the results displayed are different. That is because the elevation of the pipeline and the pipeline is the elevation of the center of the line or pipe. When we talk about the height of the pipeline, we regard the pipeline as a line. However, if the air duct is used, the method for representing the elevation is somewhat different. The bottom elevation, the center elevation and the top elevation of the duct should be mentioned. Therefore, before the air duct, it is necessary to see whether the air duct on the drawing will be flush at the top, at the bottom, or at the bottom, or on the center, and adjust the bottom elevation, center elevation and top elevation of the duct accordingly. (in addition, when doing duct conversion, we should also use the corresponding one).
Now to do a good job in the conversion of air duct, the following aspects should be input: first, the material of the air duct; second, the wall thickness of the air duct; third, the interface type of the air duct; fourth, the insulation thickness of the air duct. It is better to read the description of these parameters, if not, refer to the relevant provisions of 05n4-3.
2、 Drawing of air valve and matters needing attention
The air valve can be converted or drawn directly. The method can refer to the conversion equipment. Here is a special part of the air valve. In the pipeline specialty, the valve does not deduct the length of the pipe, but in the air pipe, the air valve should deduct the length of the air pipe. There are different deduction methods for different types of air valve. As shown in the figure below, in some cases, no matter what the width of the air duct is, the air valve is only fixed with a fixed value; in some cases, the length of the air valve is fixed plus the height (or radius) of the air duct; in another case, there is a corresponding relationship between the width of the air duct and the length of the air valve. We can select different types of air valves according to the specific instructions. 上一篇：濟南酒店廚房排煙罩是種類是什么嗎?